Gavin Hamill <gdh@laterooms.com> writes:
> OK, having moved from our quad-xeon to an 8-CPU IBM pSeries 650
> (8x1.45GHz POWER4 instead of 4 x 3GHz Xeon), our query times have shot
> up and our website is next to unusable. The IBM is not swapping (not
> with 16GB of RAM!), disk i/o is low, but there must be something
> critically wrong for this monster to be performing so badly..
Have you vacuumed/analyzed since reloading your data? Compare some
EXPLAIN ANALYZE outputs for identical queries on the two machines,
that usually helps figure out what's wrong.
regards, tom lane